Flotation process



Patented Dec. '7, 1937 UNITED STATES FLOTATION PROCESS Herbert P. A. Groll, Oakland, Calif., assignor to Shell Development Company, San Francisco, Calif., a corporation of Delaware No Drawing. Application August 28, 1933, Serial No. 687,196

I 8 Claims.

In my copending application, Serial No. 654,253, filed January 30, 1933, of which this case is a continuation-in-part, I have described the production of novel compounds, i. e. unsaturated xanthates of alcohols containing at least four carbon atoms to the molecule. Amongst others, I have described isobutenyl xanthate, pentenyl and hexenyl xanthates and the like.

I have discovered that these compounds,

10 whether of straight chain or forked chain character, are useful in flotation processes as prometers, particularly in froth flotation operations.

The alkali-metal salts of these unsaturated xanthic acids, particularly the sodium and potassium salts are most preferred.

The promoters may be utilized with any of the well-known accessoryreagents such as depressors, regulators, frothers and activators. The unsaturated xanthates permit operation in an alkaline medium andare preferably added in the form of a solution. The unsaturated xanthates may be used alone or with other promoters, including the use of two or more unsaturated xanthates.

Example 1 A free milling gold ore of a value of $33.60 per ton, 90% of the gold being present in the free state, was ground to less than 65 mesh. The pulverized ore was subjected to a standard flotation operation using 0.1 lb. isobutenyl xanthate and 0.005 lb. pine oil per ton for a period of nine minutes. 4.17% of concentrate were recovered having avalue of $469.60 per ton. The tailings contained gold to the value of $8.00 per ton.

Example 2 The same ore as used in Example 1 was treated under the same conditions, but using a mixture of primary and secondary lso-octenyl xanthate. The concentrate in this case amounted to 4.70% having a value of $412.00 per ton, the. tailings having a value of $9.60 per ton.

Besides the unsaturated xanthates, previously 5 mentioned, I may use primary and/or secondary unsaturated xanthates such as allyl xanthate, crotyl xanthate, primary isopentenyl xanthate, isopropenyl methyl carbinyl xanthate, cyclohexenyl xanthate, phenyl, isoprope'nyl carbinyl 50 xanthate, etc. as flotation promoters, the particular promoter being more or less dependent on the character of the ore undergoing treatment, the mineral content thereof, the hydrogenion concentration of the liquid, the tendency of .55 the gangue materials to be carried along with the froth, etc. Those containing at least four carbon atoms to the molecule are particularly suitable for certain ores and those containing an unsaturated tertiary carbon atom directly linked to the carbinol group are especially 5 desirable.

Copper, zinc, lead and similar ores also may be treated with my novel promoters.

I claim as my invention:

1. A method of recovering minerals from ores 10 which comprises subjecting an ore to a'froth flotation operation in the presenceof an isoalkenyl xanthate.

2. A methodof recovering minerals from ores which comprises subjecting an ore to a froth 1 flotation operation in the presence of an unsaturated aliphatic xanthate containing not more than live carbon atoms in the aliphatic radical.

3. A method of recovering minerals from ores which comprises subjecting an ore to a froth flotation operation in the presence of an unsaturated aliphatic xanthate containing four carbon atoms to the molecule.

4. A method of recovering minerals from ores which comprises subjecting an ore to a froth flotation. operation in the presence of isobutenyl xanthate.

5. A method of recovering minerals from ores 7 which comprises subjecting an ore to a froth flotation operation in the presence of a xanthate 30 of an unsaturated alcohol containing an unsat- 'uratcd tertiary carbon atom linked directly to flotation operation in the presence of anunsaturated xanthate of the general formula R0C|SM wherein R represents an isoalkenyl radical, an alkenyl radical at least one hydrogen atom of which is substituted by a cyclic .organic radical,

or a straight chain alkenyl radical containing less than six carbon atoms, and M represents a metal.

naasnar P. A. (mom. 

